The invention relates generally to the field of custom fitted footgear: dress shoes, athletic boots, sneakers, running shoes, orthopedic shoes, and the like, and more particularly to an improved means for accomplishing same.
Modern living demands walking and running on unnatural hard, flat surfaces in footgear manufactured on lasts contoured to a non-existant "average foot", said lasts being further distorted by considerations of style.
Because of the many variables in the shape and contours of feet, as well as footgear, of the same size, it has been estimated that approximately 70% of people are fitted poorly and that often the entire weight is supported on two small areas of the foot. This causes an unbalanced, unsteady gait which often results in tired and painful feet and legs as well as other discomforts and deformities that can extend up through the back and the entire body.
It is known in the art to control postural problems of the individual foot by various means worn inside footgear. However, each of said means has its own advantage and disadvantage.
Doctors of Podiatry, among others, make effective rigid and simi-rigid "Foot Orthotics" over positive Plaster of Paris casts of a patient's foot, said cast being taken in a neutral attitude. This is a lengthy and costly process, requiring the services of highly trained personnel to take the casts and laboratories to fabricate the Orthotic, after which adjustments have to be made to ccmpensate for dynamic problems which the static cast cannot duplicate. Further, a hard cast cannot properly reproduce the differences between thin-skinned and fat feet which influences the result. The process takes several weeks to complete. Further, Orthotics cannot be worn in all footgear, and especially not in most ladies dress shoes.
To overcome the necessity of trained personnel and an involved and expensive process, various other methods of achieving foot balance and the distribution weight and support are known in the art. One is the well known "arch support" which is made of leather and foam, or leather and spring steel sections, and the like. These are offered in shoe sizes, with high, low, and medium differences in height. They have the advantage of being fitted "off the shelf".
Other means of changing the inner contours of footgear involve molding the interior of the footgear to permanently reflect the shape of the individual foot. This is achieved by placing an envelope containing a mix of molding material into the footgear, or by injecting same, said molding material quickly setting or hardening.
These and other methods achieve relatively small benefits because they are based on the erroneous popular belief that foot and body comfort can the achieved by supporting the medial long arch of the foot. Visually and anatomically, this is obviously false. Visual inspection of a wet foot print will show that the foot makes ground contact only at the heel and ball area. In some cases, there may be some contact along the lateral border of the foot. The "arch" of the foot not making contact is made up of several Tarsal bones, which are squarish in configuration, and very rough for ligamentous attachments. Pressures under this area are uncomfortable or painful.
Most "supports", whether pre-made or molded, can only be worn because they are not high enough to support the arch area. If they reach the arch area, they can only be worn after they are "broken-in", which in reality means when the shank of the footgear underlying this area has been broken down.
Further, a larger size of footgear is required to accept such "support", and most dress shoes, especially ladies', cannot accept them in any way.
Further, any method of injecting molding material requires the use of some bag-like device to contain the molding material, said bag-like device is usually connected directly to the opening means for the injection of said molding material, thus limiting choice of area for said bags and said opening. The disadvantages of other means of placing said bags and said openings apart are discussed further on.
Further, because of the many variables in feet and footgear of the same size, often only one part of the foot may benefit from said supports.
Any benefits from the use of such means are due to the incidental haphazard support at the front and back areas of the means, namely the medial and lateral areas just distal (forward) of the dependent part of the heel bone, and the area just proximal (behind) to the heads of the Metatarsal bones. The bones in these areas are smooth enough to accept pressure and thus distribute the body weight over a larger area. Further benefit occurs because these areas are over parts of the footgear, the heel and sole, that are in direct contact with the ground so that there will be no breakdown of the footgear to cause loss of supportive action.
To retain and improve upon the above benefits, while eliminating the disadvantages, attempts have been made to control separate areas of the footgear individually.
The present, inventor has contributed to the art of molding individual areas of footgear with several U.S. Patents namely U.S. Pat. No. 3,903,621, 3,736,673 and particularly 3,444,586,which teach the use of multiple individual elements located in pertinent areas of footgear, each of said elements comprising a flexible bag and a connecting tube connecting said bag to an end piece. Said end pieces are constructed to engage the unique nozzle of an injecting gun, said gun having a rotating nozzle to inject a mix of molding material into each element in turn, and, by continuing to rotate, to close off the individual end piece while the molding material sets.
While this method and others were an improvement in that they were designed to mold several individual areas of the footgear, they also had several decided disadvantages.
As with all molding materials intended to "set" within a prescribed time, the reaction is set in motion by the mixing of two or more ingredients. Various factors, such as improper mixing, change in reaction time due to shelf life, etc., often resulted in uncertain setting times. If the time was too fast, the resulting mix might not flow easily through the connecting tubes. If the time was too slow, the mold could be walked on too soon and thus be depressed and not achieve its supportive effect.
Further, if too much molding material was injected into the bags, it was not possible to withdraw the overage. Further, the foot had to be at rest to receive the molding material after which it had to set before it could be tested dynamically by walking or running. At that time, if too much or too little of the material had been injected, it was not possible to correct the situation.
Further, such a molding mix had a viscosity that required that the connecting tube between the injections gun and the retaining bag be of such size that a foot fitted over them would be painfully aware of said connecting tube. Therefore, grooves must be cut out of the sole of the footgear to receive them. This required that this method of individual molding must be manufactured into the footgear, with all its resulting problems of design, marketing, financing, etc.
Further, because of its size, the connnecting area for the end pieces of the elements and the nozzle of the injection gun could only be located in the shank area of the sole of the footgear. This interferred with the construction of this important area of footgear.
Further, fabrication of said injection gun was complicated and expensive, and cleaning of said gun between usages difficult and time consuming.
Further, as with all molding methods, the positioning of the leg and thigh was crucial to a proper molding. Control of the extremities was difficult because of the shank location of said gun and end part pieces.
Further, if at a later time the foot changed, it was not possible to make any changes in the "set" mold.
It is, therefore, among the principle assets of the present invention to provide an improved means for molding footgear for the individual foot, in which the above-mentioned disadvantges and difficulties have been substantially eliminated.
Another object of the invention lies in the provision of means for molding the important areas of footgear to an individual foot, both statically and dynamically, within a few minutes, said means being such that it can be used by any shoe clerk, or even the wearer himself, in a quick, neat, clean and inexpensive manner, which means also permit the correction of mistakes.
Another object of the invention lies in the provision for the use of a molding material that will not set, and, therefore, will not require any mixing of ingredients, such non-setting material making possible the easy addition or withdrawal of molding material to insure proper fit at any time.
Another object of the invention lies in the provision of means that would easily permit its addition to already manufactured footgear.
Another object lies in the provision of means that would permit the portals of entry of the molding material to be located at a variety of areas of the footgear, said areas to be chosen mainly for ease of accessability.
Another feature of the invention lies in the fact that the inventive means may be employed in a wide variety of footgear ranging from sneakers, boots, fashionable dress shoes, orthopedic shoes, and the like, without requiring change of size of said footgear.
Another feature of the invention permits the use of injection apparatus presently, easily, and inexpensively available.